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|
/*
This file is part of solidity.
solidity is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
solidity is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with solidity. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* Unit tests for the SMT checker.
*/
#include <test/libsolidity/AnalysisFramework.h>
#include <boost/test/unit_test.hpp>
#include <string>
using namespace std;
namespace dev
{
namespace solidity
{
namespace test
{
class SMTCheckerFramework: public AnalysisFramework
{
public:
SMTCheckerFramework()
{
m_warningsToFilter.push_back("Experimental features are turned on.");
}
protected:
virtual std::pair<SourceUnit const*, std::shared_ptr<Error const>>
parseAnalyseAndReturnError(
std::string const& _source,
bool _reportWarnings = false,
bool _insertVersionPragma = true,
bool _allowMultipleErrors = false
)
{
return AnalysisFramework::parseAnalyseAndReturnError(
"pragma experimental SMTChecker;\n" + _source,
_reportWarnings,
_insertVersionPragma,
_allowMultipleErrors
);
}
};
BOOST_FIXTURE_TEST_SUITE(SMTChecker, SMTCheckerFramework)
BOOST_AUTO_TEST_CASE(smoke_test)
{
string text = R"(
contract C { }
)";
CHECK_SUCCESS_NO_WARNINGS(text);
}
BOOST_AUTO_TEST_CASE(simple_overflow)
{
string text = R"(
contract C {
function f(uint a, uint b) public pure returns (uint) { return a + b; }
}
)";
CHECK_WARNING(text, "Overflow (resulting value larger than");
}
BOOST_AUTO_TEST_CASE(warn_on_typecast)
{
string text = R"(
contract C {
function f() public pure returns (uint) {
return uint8(1);
}
}
)";
CHECK_WARNING(text, "Assertion checker does not yet implement this expression.");
}
BOOST_AUTO_TEST_CASE(warn_on_struct)
{
string text = R"(
contract C {
struct A { uint a; uint b; }
function f() public pure returns (A) {
return A({ a: 1, b: 2 });
}
}
)";
/// Multiple warnings, should check for: Assertion checker does not yet implement this expression.
CHECK_WARNING_ALLOW_MULTI(text, "");
}
BOOST_AUTO_TEST_CASE(simple_assert)
{
string text = R"(
contract C {
function f(uint a) public pure { assert(a == 2); }
}
)";
CHECK_WARNING(text, "Assertion violation happens here for");
}
BOOST_AUTO_TEST_CASE(simple_assert_with_require)
{
string text = R"(
contract C {
function f(uint a) public pure { require(a < 10); assert(a < 20); }
}
)";
CHECK_SUCCESS_NO_WARNINGS(text);
}
BOOST_AUTO_TEST_CASE(assignment_in_declaration)
{
string text = R"(
contract C {
function f() public pure { uint a = 2; assert(a == 2); }
}
)";
CHECK_SUCCESS_NO_WARNINGS(text);
}
BOOST_AUTO_TEST_CASE(use_before_declaration)
{
string text = R"(
contract C {
function f() public pure { a = 3; uint a = 2; assert(a == 2); }
}
)";
CHECK_SUCCESS_NO_WARNINGS(text);
text = R"(
contract C {
function f() public pure { assert(a == 0); uint a = 2; assert(a == 2); }
}
)";
CHECK_SUCCESS_NO_WARNINGS(text);
}
BOOST_AUTO_TEST_CASE(function_call_does_not_clear_local_vars)
{
string text = R"(
contract C {
function f() public {
uint a = 3;
this.f();
assert(a == 3);
f();
assert(a == 3);
}
}
)";
CHECK_SUCCESS_NO_WARNINGS(text);
}
BOOST_AUTO_TEST_CASE(branches_clear_variables)
{
// Only clears accessed variables
string text = R"(
contract C {
function f(uint x) public pure {
uint a = 3;
if (x > 10) {
}
assert(a == 3);
}
}
)";
CHECK_SUCCESS_NO_WARNINGS(text);
// It is just a plain clear and will not combine branches.
text = R"(
contract C {
function f(uint x) public pure {
uint a = 3;
if (x > 10) {
a = 3;
}
assert(a == 3);
}
}
)";
CHECK_WARNING(text, "Assertion violation happens here");
// Clear also works on the else branch
text = R"(
contract C {
function f(uint x) public pure {
uint a = 3;
if (x > 10) {
} else {
a = 3;
}
assert(a == 3);
}
}
)";
CHECK_WARNING(text, "Assertion violation happens here");
// Variable is not cleared, if it is only read.
text = R"(
contract C {
function f(uint x) public pure {
uint a = 3;
if (x > 10) {
assert(a == 3);
} else {
assert(a == 3);
}
assert(a == 3);
}
}
)";
CHECK_SUCCESS_NO_WARNINGS(text);
}
BOOST_AUTO_TEST_CASE(branches_assert_condition)
{
string text = R"(
contract C {
function f(uint x) public pure {
if (x > 10) {
assert(x > 9);
}
else
{
assert(x < 11);
}
}
}
)";
CHECK_SUCCESS_NO_WARNINGS(text);
text = R"(
contract C {
function f(uint x) public pure {
if (x > 10) {
assert(x > 9);
}
else if (x > 2)
{
assert(x <= 10 && x > 2);
}
else
{
assert(0 <= x && x <= 2);
}
}
}
)";
CHECK_SUCCESS_NO_WARNINGS(text);
}
BOOST_AUTO_TEST_CASE(ways_to_clear_variables)
{
string text = R"(
contract C {
function f(uint x) public pure {
uint a = 3;
if (x > 10) {
a++;
}
assert(a == 3);
}
}
)";
text = R"(
contract C {
function f(uint x) public pure {
uint a = 3;
if (x > 10) {
++a;
}
assert(a == 3);
}
}
)";
CHECK_WARNING(text, "Assertion violation happens here");
text = R"(
contract C {
function f(uint x) public pure {
uint a = 3;
if (x > 10) {
a = 5;
}
assert(a == 3);
}
}
)";
CHECK_WARNING(text, "Assertion violation happens here");
}
BOOST_AUTO_TEST_CASE(while_loop_simple)
{
// Check that variables are cleared
string text = R"(
contract C {
function f(uint x) public pure {
x = 2;
while (x > 1) {
x = 2;
}
assert(x == 2);
}
}
)";
CHECK_WARNING(text, "Assertion violation happens here");
// Check that condition is assumed.
text = R"(
contract C {
function f(uint x) public pure {
while (x == 2) {
assert(x == 2);
}
}
}
)";
CHECK_SUCCESS_NO_WARNINGS(text);
// Check that condition is not assumed after the body anymore
text = R"(
contract C {
function f(uint x) public pure {
while (x == 2) {
}
assert(x == 2);
}
}
)";
CHECK_WARNING(text, "Assertion violation happens here");
// Check that negation of condition is not assumed after the body anymore
text = R"(
contract C {
function f(uint x) public pure {
while (x == 2) {
}
assert(x != 2);
}
}
)";
CHECK_WARNING(text, "Assertion violation happens here");
// Check that side-effects of condition are taken into account
text = R"(
contract C {
function f(uint x) public pure {
x = 7;
while ((x = 5) > 0) {
}
assert(x == 7);
}
}
)";
CHECK_WARNING(text, "Assertion violation happens here");
}
BOOST_AUTO_TEST_CASE(constant_condition)
{
string text = R"(
contract C {
function f(uint x) public pure {
if (x >= 0) { revert(); }
}
}
)";
CHECK_WARNING(text, "Condition is always true");
text = R"(
contract C {
function f(uint x) public pure {
if (x >= 10) { if (x < 10) { revert(); } }
}
}
)";
CHECK_WARNING(text, "Condition is always false");
// a plain literal constant is fine
text = R"(
contract C {
function f(uint) public pure {
if (true) { revert(); }
}
}
)";
CHECK_SUCCESS_NO_WARNINGS(text);
}
BOOST_AUTO_TEST_CASE(for_loop)
{
string text = R"(
contract C {
function f(uint x) public pure {
require(x == 2);
for (;;) {}
assert(x == 2);
}
}
)";
CHECK_SUCCESS_NO_WARNINGS(text);
text = R"(
contract C {
function f(uint x) public pure {
for (; x == 2; ) {
assert(x == 2);
}
}
}
)";
CHECK_SUCCESS_NO_WARNINGS(text);
text = R"(
contract C {
function f(uint x) public pure {
for (uint y = 2; x < 10; ) {
assert(y == 2);
}
}
}
)";
CHECK_SUCCESS_NO_WARNINGS(text);
text = R"(
contract C {
function f(uint x) public pure {
for (uint y = 2; x < 10; y = 3) {
assert(y == 2);
}
}
}
)";
CHECK_WARNING(text, "Assertion violation");
text = R"(
contract C {
function f(uint x) public pure {
for (uint y = 2; x < 10; ) {
y = 3;
}
assert(y == 3);
}
}
)";
CHECK_WARNING(text, "Assertion violation");
text = R"(
contract C {
function f(uint x) public pure {
for (uint y = 2; x < 10; ) {
y = 3;
}
assert(y == 2);
}
}
)";
CHECK_WARNING(text, "Assertion violation");
}
BOOST_AUTO_TEST_SUITE_END()
}
}
}
|
